Roller bit



Patented Dec. 13, 1921.

UNITED STATES PATENT OFFICE.

CLINTON H. I. BULL, OF HOUSTON, TEXAS, ASSIGNOR TO REED ROLLER BIT COMPANY, 01' HOUSTON, TEXAS, A CORPORATION 01' TEXAS.

ROLLER IBIT.

Application filed June 2, 1927. Serial No. 195,931.

This invention relates to drills and more particularly to roller bits.

In the use of roller cutters of the general type of which this invention is an improve- 5 ment, much difliculty has heretofore been encountered in the mounting and removal and in the lubrication thereof.

It is the object of the present invention to provide new and improved cooperative elements whereby the assembly of roller cutters is greatly simplified, and eflicient lubrication thereof insured.

The accompanying drawings are illustrative of the preferred embodiment of the invention. Flg. 1 thereof is a fragmentary side elevation, partly in section, of the parts assembled on the bit head; and Fig. 2 is a section on the line 2-2 of Fig. 1.

In the drawings, a part of the bit head is indicated at 1, and is fprovided with the usual inclined bottom sur ace 2, which, together with a like surface on the other side of the head not shown), defines a substantially V- shape recess in the bottom of the head for the rece tion of the roller cutters. A screwthread spindle 1 projects inwardly and downwardly from said surface. A bushing 3 is screwed on said spindle, and a cutter 4 is rotatably locked on said bushing. Thus the indle and bushing serve as a support for t e cutter.

Those skilled in the art fully understand the general arrangement above described.

The present invention resides in the con- 85 struetion of the bushing and the cutter, and the provision of new and improved retaining means.

It will be observed that the cutter 4 has in the wall of its central recess 4', an annular 4 groove 4". K plurality of retaining devices I in the form of pins 5 are driven into suitable holes in bushing 3 and extend into groove 4" of cutter 4, thus rotatably locking the cutter on the bushing. The arts are assembled as follows: Bushing 3 aving been placed within the recess 4' of cutter 4, it is rotated therein until one of the holes is brought to a position immediately opposite the opening 4 in cutter 4. One of the pins 5 is then inserted through opening 4 and part way into said hole. The holes are preferably made of such size with respect to the pins that the pins fit snugly therein. Any suitable tool is then used to drive pin 5 completely in. The other pins are likewise put in place. The bushing with the cutter rotatably locked thereon is then laced over spindle 1, and any suitable tool is inserted through opening 4 to temporarily lock the cutter and bushing non-rotatably together, so that bushing 3 may be screwed on spindle 1. It will be understood that when the tool is inserted, the groove 4" is obstructedand the cutter cannot, therefore, turn on the bushing.

After the bushing has been screwed on the spindle, plug 6 is screwed into the screwthreaded opening 4 to prevent the entry of foreign matter between the cutter and bushlng and also to prevent the escape of lubricant. The inner end of plug 6, when said plug is in position, is flush with the bottom of groove 4".

Grease is forced into groove 4 through opening 4, and the groove 4", bushing 3 and retaining devices 5 form a plurality of grease chambers whereby the device is efliciently lubricated.

The removal of pins 5 may be effected by any suitable tool adapted to be inserted through opening 4 and to be connected with said pins. The pins are shown provided with screw-threaded sockets in their outer ends. A tool having a screw-threaded end may be passed through hole 4 and its end screwed into said sockets.

I claim:

1. In a drill, a head, a spindle on said head, a bushing on saidv spindle, a cutter on said bushing, said cutter having a groove therein, and a retaining device secured to said bushing and extending into the groove in said cutter to rotatably lock said cutter on said bushin 2. In a drill, a head, a s indle on said head, a bushing on said spin le, a cutter on said bushing, said cutter having a groove therein, and a plurality of pins secured to said bushing and extending into the groove in said cutter to rotatably lock said cutter on said bushing.

3. In a drill, a head, a spindle on said head, a bushing on said spindle, a cutter on said bushing, said cutter having a groove therein, and a removable retaining device secured to said bushing and extending into the cove in said cutter to rotatably lock said cutter on said bushing.

4. In a drill, a head, a spindle on said head, a bushing on said spindle, a cutter on said bushing, said cutter having a groove therein, and a plurality of removable pins secured to said bushing and extending into the groove in said cutter to rotatably lock said cutter on said bushing.

5. In a drill, a head, acutter support on said head, a cutter on said support, said cutter having a groove in the inner surface thereof and an opening in the side thereof. and a retaining device secured to said support and extending into the groove in said cutter to rotatahlv lock said cutter on said support, said retaining device being insertible in and removable from said support through said opening.

6. In a drill. a head, a cutter support on said head. a cutter on said support. said cutter having a groove in the inner surface thereof and an opening in the side thereof, and a plurality of pins secured to said support and extending into the groove in said cutter to rotatably lock said cutter on said support, said pluralitv of pins being insertible in and removable from said support through said opening.

7. In a drill, a head, a spindle on said head, a bushing on said spindle, a cutter on said bushing, said cutter havin a groove therein and an opening in the side thereof, and a retainin device secured to said bushing and exten ing into said groove to rotatably lock the cutter on the bushing, said device being adapted to be engaged by a tool inserted through said opening, whereby the cutter may be non-rotatably locked on said bushing.

8. In a drill, a head, a cutter support on said head, a cutter on said support, said cutter having an'internal annular groove and an openin 1n the side thereof, and a retaining pin a apted to engage said support and extend into said groove to rotatablv lock said cutter on said support. said pin being movable through said opening.

9. In a drill, a head. a cutter support on said head, said cutter support havin a hole therein, a cutter on said support, sai cutter having an internal annular groove and an opening in the side thereof, and a pin fitting in said hole and extending into said groove to rotatably lock said cutter on said bushing, said pin being movable through said opening.

CLINTON H. M. BULL. 

